1. Field of the Invention
This invention relates to horology and especially to watches having stop/start and/or reset functions.
In particular, this invention concerns a trigger mechanism for mechanically actuating the chronograph functions of a watch.
2. Description of Related Art
Chronograph watches typically include one or more pushbuttons, pushers, depressors, pressure switches, or equivalent devices, mounted for movement relative to a watchcase within which is housed a watch movement including one or more elements that are adapted to be actuated by the operation of the one or more pushbuttons, for example, as shown in U.S. Pat. No. 4,364,674 and U.S. published application no. US2006/0164922. This arrangement is generally found in both mechanical and electronic watches for operating the various functions, such as the stop/start systems in stopwatches and the time display systems in electronic watches.
The pushbuttons are typically actuated manually by finger manipulation. This procedure does not readily achieve precision timing as may be needed for sporting events and similar activities. In manually operated chronographs the flesh surrounding the finger-tip cushions the actuation of the pushbutton and may cause variations in timing precision. Also, gloves covering the finger tip, can create timing imprecision.
An attempt to enhance stopwatch precision is shown in U.S. Pat. No. 5,224,077, however, the device of that patent is not an integral part of the watchcase and is cumbersome to use.
Another timepiece, shown in U.S. Pat. No. 3,759,033, is intended to actuate a pushbutton by use of a pivotal key. That device however, does not apply mechanical linkage for transforming the movement of the key into a reciprocal movement for actuating the pushbutton for improved precision as in the present invention.
A further device for operating a chronograph is disclosed in U.S. Pat. No. 7,570,545. The rocker mechanism of that device lacks the precision control achievable with the present invention.